The fediverse isn’t over engineered, it’s just not quite focused on the right aspects. A federated social network needs to be more like a block chain, where the content is centralized, and the instances (miners) are decentralized. The content is the important part, and with everything being tied to an instance, it makes the content harder to access. You have instances defederating, going down, closing, and version conflicts, all that makes it harder for a network to gain traction.